I keep returning to the Harvard Study of Adult Development and the book about it called Triumphs of Experience. There are so many interesting findings in that study, that I decided to break it up into a few blog posts. Go here for an overview about the study if you are unfamiliar with it.

As I read the book and all the hundreds of conclusions in it, I was struck by how much in your life fate that seems determined by your relationship with your parents. Here are some interesting correlations that are statistically proven, but that seem kind of unintuitive and hard to explain. I am very curious about these correlations, and it would be interesting to one day find explanations for them. Also, remember, as always, that correlation does not prove causation.

A warm childhood relationship with your mother

Is significantly associated with high IQ in college

Is also significantly associated with your mental competency at age 80

Is significantly associated with a high income in late life

A poor childhood relationship with your mother

Is very significantly associated with dementia at age 80

A warm childhood relationship with your father

Is associated with your contentment with life in your 70's

Is associated with lower anxiety. A significantly lower standing pulse rate in college, for example, and fewer physical and mental symptoms under stress in young adulthood.

A poor childhood relationship with your father

Is significantly associated with poor marriage (and therefore an unhappy life in general)

The mysterious connection to maternal grandfather's age of death

An extremely unintuitive finding in the grant study was that the age of death of the maternal grandfather (MGF) had a strong connection to anxiety and affective disorder.

The mean age of death of the MGF of the clearly depressed men in the study was 60. Compared to undistressed men whose MGF passed away at age 75 on average. If we look at the 10 men in the study with the highest anxiety scores, the age of death of the MGF was 57. Compare this to the 10 men with the lowest anxiety scores, where the age of death of the MGF was 83. A huge difference and most likely more than just a coincidence.

So there is still this mystery as to why an early death of the maternal grandfather is correlated with affective disorder. One theory is that it is genetic, and that anxiety is associated with all kinds of unnatural early deaths, and that some of these disorders might be inherited more strongly from the maternal grandfather. But the jury is still out on this one.